Pulsating suction cleaner with oscillating beater



INVENTOR.

Nov. 4, 1958 A. e. BODINE, JR 4 I PULSATING SUCTION CLEANER WITH OSCILLATING BEATER Flled July 30, 1953 PULSATING SUCTION CLEANER WITH OSCILLATIN G BEATER Albert G. Bodine, Jr., Van Nuys, Calif.

Application July 30, 1953, Serial No. 371,245

4 Claims. (Cl. 15-382) This invention relates generally to suction cleaners for rugs and the like, and more particularly to suction cleaners of a novel type employing a pulsating suction air flow and an oscillating beater.

In my copending application entitled Vacuum Cleaner With Pulsating Suction, filed June 23, 1953, Serial No. 363,516, I disclosed several forms of pulsating suction cleaners. The present invention resembles those cleaners in certain general respects, at least to the extent of applying a pulsating suction to the rug, with the advantage of thereby securing an improved rug cleaning action, wherein the rug is vibrated bodily and its individual threads or fibers are vibrated individually, so as to give a very rapid working action which is especially effective in loosening and removing dirt from the fabric. The general purpose of the present invention is to provide a pulsating suction cleaner having all of the advantages of these previously described cleaners and having, in addition an oscillating rug beater element which rapidly thumps the rug in step with the periodicity of the suction pulsations.

In accordance with the invention, considered broadly, the oscillating beater co-acts with the suction developed within the cleaners nozzle to vibrate the rug. In more particular, a suction nozzle is provided, and its orifice leads to a chamber communicating via a neck member with the usual tubular wand through which the suction is applied. Mounted in this nozzle is an oscillating beater, typically in the form of a vertically guided blade, the lower edge of which is engageable with the rug area within the confines of the nozzle. The upper portion of this blade is connected to a flexible diaphragm which extends across the said nozzle chamber, and, in effect, forms one defining wall of the latter. Spring means hold the diaphragm and blade in a normal position elevated somewhat above the rug area which is in contact with the nozzle. In operation, suction developed in the suction line first elevates the rug from the floor slightly so as to engage the nozzle, thus closing off the nozzle orifice and permitting the nozzle chamber to be evacuated. Evacuation occurs almost instantly, pulling the diaphragm sharply down, and so driving the oscillatory beater downward against the rug. This drives the rug down toward the floor, breaking it free from the nozzle, and the suction which has been developed inside the chamber is then satisfied by atmospheric air, so that the diaphragm and beater are then pulled upwardly by their spring. A sufficiently reduced pressure remains within the chamber, however, that upon such elevation of the beater, the rug is immediately sucked upwardly against the nozzle, permitting reevacuation of the chamber, and the cycle thus described repeats itself at a frequency of many times per second, depending upon the design constants of the apparatus.

In a preferred form of the invention, the oscillatory system consisting of the oscillating blade and its spring means is tuned to be resonant to the frequency at which the system as a Whole tends to operate. With such resited States Patent onant tuning, the beater blade tends towards oscillation with simple harmonic motion, and increased power and stability are achieved.

The invention will be more fully understood from the following detailed description of a present illustrative embodiment thereof, reference for this purpose being had to the accompanying drawings in which:

Figure l is a front elevational view of a suction cleaner embodying the invention;

Figure 2 is a rear elevational view thereof;

Figure 3 is an end elevational view thereof; and

Figure 4 is a section taken on line 44 of Figure l.

The suction-cleaner is shown to have a housing 10 providing a generally vertical disposed, laterally extended nozzle portion 11, constricted towards its lower end so as tobe formed. at the bottom with a relatively narrow, elongate orifice 12, the rearward side of the housing being formed with a tubular extension 13, preferably somewhat constricted at 13a, to which is joined the conventional tubular wand I4 understood to be connected to the suction line. The nozzle 11 encloses a suction chamber 15 indirect communication with its orifice 12, and this chamber 15 communicates with the suction passage in tubular extension 13 by way of a laterally extended port 16 (see Figs. Zand 4).

The nozzle orifice 12 is boundedby a continuous seat on the lower marginal rim of the nozzle, and in the operation of the cleaner, the rug or fabric F is sucked periodically upwardly a short distance above the flooi' surface 18 into engagement with this seat, as shown in Fig. 4'. Means are provided to maintain this seat at a distance above the floor surface 18 sufficient to permit this reciprocation of the rug, and for this purpose, I may provide any form of runner means such as wheels, skids or the like. In the present illustrative embodiment, I provide such runner means in the form of skids 19 on the endportions of the nozzle. The seat on the lower rim of the nozzle is thus, in the illustrative embodiment, defined by horizontal seating surfaces 20, of proper spacing from the floor surface, and extending nearly the full length of the nozzle, the surfaces 20 merging near the ends of the nozzle by means of flared surfaces 20a with the lower or rugengaging surfaces of the skids 19-, as clearly shown in the various figures of the drawings. Accordingly, upon suction being developed within the chamber 15, the rug area within the confines of the nozzle orifice is pulled upwardly into engagement with the seating surfaces 20 and 20a, and remains pressed down at the ends of the nozzle by the skid elements 19.

Across the top of. the chamber 15 is installed a flexible diaphragm 24, which. may be composed of various materials, and may be formed of thin, resilient sheet metal, though I prefer a lighter material such as conventional neoprene-impregnated diaphragm fabric of cotton or nylon of a typical thickness of .015". The edges of this diaphragm engage a seat 25 formed at the top of the nozzle casting, and a cap 26 is secured to this seat 25 over the diaphragm so as to enclose a chamber space 27 above the diaphragm vented to atmosphere by means of vent hole 28. This cap is secured down to the nozzle housing by means of cap screws 29, as indicated.

A vertically disposed oscillatory blade 30 is centrally mounted in nozzle chamber 15 on the flexible diaphragm 24, and extends practically the full length of the narrow elongate nozzle orifice, so as to be in relatively close spaced relation to the longitudinal nozzle edges or seats 20, 20a, its vertical end edges being guided by vertical guide slots 32 formed in the end Wall portions 33 of the nozzle. The central portion of the diaphragm 24 is stiffened by a backing plate 35 mounted against its upper surface, and screws 36 extend through this plate 35 and the diaphragm 24 to engage threaded sockets 37 provided n the upper edge of the blade member 30. Coil springs 39 connected at their lower ends to the heads of these screws 36 are accommodated within pockets 40 formed on the top of cap 26 and are adjustably connected to the upper end walls of said pockets, as conventionally indicated at 41. The springs 39 are preferably relatively stiff, so as to function as both tension and compression springs. For the present, however, they will be described and considered simply as tension springs. The blade 30 is preferably fabricated from a suitable durable but light material, such as a conventional phenolic. The lower edge 42 of this blade 30 is horizontal, and, in the form as here illustrated, the tension springs 39 normally support the diaphragm 24 and blade 30 in the position illustrated in Fig. 4, at an elevation somewhat above the nozzle seating surfaces 20.

Operation is as follows: At the start, the blade is in its upwardly retracted application of the nozzle to the rug, and development of suction in the line connected to the wand 14, pressure is sufficiently reduced within chamber 15 and nozzle orifice 12 to suck the rug upwardly against the nozzle seating surfaces 20 and 20a, as in Fig. 4. With this effective closure of the nozzle orifice by the rug the chamber 15 is almost instantly further evacuated to a substantial extent, and the differential of pressures then existing on opposite sides of the diaphragm 24 pulls said diaphragm sharply downward against its restraining spring 39, thus driving the blade 30 sharply downward against the rug. The blow thus struck against the elevated rug by the blade 30 by reason of the relatively close proximity of the lower blade edge to the nozzle seat 20, forces the rug downward and out of engagement with the nozzle seat 20, thus admitting atmospheric air to chamber 15. The pressure within chamber 15 accordingly rises rapidly towards atmospheric, causing elevation of diaphragm 24 and blade 30. Atmospheric pressure is not attained within the chamber 15, however, because of the continuing suction applied by the suction line; and the elevation of blade 30 is followed by re-elevation of the rug into re-engagement with the nozzle seat 20. Thus the cycle is completed, and this cycle is repeated over and over in rapid succession at a periodicity which will be governed by various design constants involved in the system, such as the mass of the blade 30 and diaphragm 24, the stiifness of spring 39, the volume of chamber 15, the constriction at 16, and the suction developed by the suction motor connected to the suction line. The frequency of operation may also be influenced to an extent by the character of the rug being cleaned.

It is possible to achieve an improvement in operation by tuning the oscillatory system consisting of blade 30, diaphragm 24 and springs 39 to the period at which the other factors or components of the system tend to operate best or most naturally. Also, resonance in the oscillatory system is promoted by use of springs 39 capable of acting as both tension and compression springs, so that the energy stored by said springs on the latter portion of the up-stroke of the diaphragm and blade will be returned to start the diaphragm and blade on the down stroke. A similar effect may be achieved by using an elastic substance for the diaphragm 24. Thus the diaphragm and blade are set into substantially harmonic oscillation at a resonant frequency governed by the mass and stiffness constants of the oscillatory components. The frequency of operation is accordingly established by the resonant frequency of the combined oscillatory system. In consequence, the behavior of the system should be further described as follows: On each down-stroke of the tuned oscillatory diaphragm and blade, which occurs partly by reason of release of energy stored in its spring elements in the up position and partly by force exerted owing to a differential of pressures below and above the diaphragm, the blade strikes and drives the. rug

position as shown in Fig. 4. Upon downward and away from the nozzle seat 20; and on each up-stroke of the diaphragm and blade, which occurs partly by reason of release of energy stored in the stressed spring elements following attainment of the lower limit of the stroke, and partly by reason of decrease of the differential of pressures on opposite sides of the diaphragm upon inrush of air into 15, the rug is re-elevated into engagement with the seat 20 by the suction still prevailing in the nozzle orifice 12. The cycle is stabilized and very greatly strengthened by so tuning the oscillatory diaphragm and blade to operate at a natural resonant frequency. The blade thus reaches a vigorous vibratory condition by over-traveling on each end of its stroke, with practically complete inter-change of energy periodically between the dynamics of motion and potential energy of spring deflection.

The rug subjected to this action will be seen to be subjected to a pulsating suction condition, occurring at a frequency of many times per second, causing it to vibrate rapidly up and down, into and out of engagement with the nozzle seating surface 20. Not only does the area of the rug within the confines of the nozzle so vibrate in a bodily manner, but individual threads, fibers and strands of the rug are caused by the pulsating suction to vibrate independently, or relatively to one another. In addition, the periodical thumping action exerted by the oscillatory blade 30 occurring at the same frequency of operation, i. e., at many times per second, subjects the rug to a vigorous beating action. The result is a dirt loosening and cleaning action of very great effectiveness.

It will be understood that the embodiment of my invention here shown is for illustrative purposes only and that various changes in design, structure and arrangement may be made without departing from the spirit and scope of the appended claims.

I claim:

1. In a suction cleaner the combination of: a hollow nozzle formed with a suction orifice defined by a peripheral rug engaging seat presented downwardly to the rug to be cleaned, means engageable with the rug in a predetermined plane for supporting said seat at a slight elevation thereabove, a vibratory diaphragm stretched across said hollow nozzle so as to form a suction chamber open at the bottom through said suction orifice, a suction line communicating with said chamber, whereby to develop suction at said orifice and adjacent the suction chamber side of said diaphragm, the opposite side of said diaphragm being isolated from said suction and exposed to substantially atmospheric pressure, and a rug heater in said nozzle operatively connected to said vibratory diaphragm and vibratable thereby against said rug at points in relatively close proximity to at least a portion of said suction orifice seat, means supporting and spring-biasing said diaphragm and beater to assume normally a first position of a rapidly repetitive cycle with said beater elevated sufiiciently to permit elevation of the rug into contact with the orifice seat by virtue of suction initially developed in said chamber, said diaphragm and beater being subsequently movable, upon development of further suction in said chamber such that a pressure differential is created across said diaphragm sufiicient to overcome said spring bias, in a direction to strike said rug at said points in relatively close proximity to said orifice seat, so as to slightly separate said rug from said seat and thereby admit atmospheric air past said seat to said suction chamber, said admitted atmospheric air reducing the pressure differential across the diaphragm sufficiently for return movement of said spring biased diaphragm and beater to said elevated position to complete said repetitive cycle.

2. The subject matter of claim 1, including an atmospherically vented chamber enclosing said opposite side of said diaphragm.

3. The subject matter of claim 1, wherein said supporting and spring-biasing means includes spring means connected to said diaphragm and wherein said spring means, diaphragm and beater comprise an oscillatory resonant system having a natural resonant frequency, such as to augment the vibration amplitude of the diaphragm and beater.

4. In a suction cleaner the combination of: a hollow nozzle formed with a suction orifice defined by a periph eral rug engaging seat presented downwardly to the rug to be cleaned, means engageable with the rug in a predetermined plane for supporting said seat at a slight elevation thereabove, a resilient vibratory diaphragm stretched across said hollow nozzle so as to form a suction chamber open at the bottom through said suction orifice, a suction line communicating with said chamber, whereby to develop suction at said orifice and adjacent the suction chamber side of said diaphragm, the opposite side of said diaphragm being isolated from said suction and exposed to substantially atmospheric pressure, and a vibratory rug beater in said nozzle operatively connected to said vibratory diaphragm for alternately upward and downward vibratory movements thereof in response to elastic vibration of said diaphragm, said vibratory beater being so disposed within said nozzle as to strike said rug at points in relatively close proximity to at least a portion of said suction orifice seaton each downward vibratory movement thereof, said diaphragm being supported by said nozzle to assume normally a first undeflected position of 6 a rapidly repetitive cycle with said beater elevated sufliciently to permit elevation of the rug into contact with the orifice seat by virtue of suction initially developed in said chamber, said diaphragm being subsequently elastically defiectible, by virtue of consequent development of further suction in said chamber such as to create a given pressure differential thereacross, to a second position of said cycle, so as to move said beater downwardly to strike said rug at said points in relatively close proximity to said orifice seat, so as to slightly separate said rug from said seat and thereby admit atmospheric air past said seat to said suction chamber, said admitted atmospheric air reducing the pressure differential across the elastically deflected diaphragm sufficiently for return movement of said diaphragm in the direction of its said first position by virtue of forces of elastic restoration therewithin, said diaphragm thereby moving said beater to said elevated position to complete said repetitive cycle.

References Cited in the file of this patent UNITED STATES PATENTS 2,031,957 Karlstrom Feb. 25, 1936 2,070,834 Karlstrom Feb. 16, 1937 2,159,164 Karlstrom May 23, 1939 2,688,763 Pfafile et al. Sept. 14, 1954 

